The following information is provided to assist the reader in understanding technologies disclosed below and the environment in which such technologies may typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding the technologies or the background thereof. The disclosure of all references cited herein are incorporated by reference.
Conventional autostereoscopic displays use arrays of lenses or parallax barriers or other view selectors to make a number of pixels of the display visible to one eye of a viewing person and to make a number of other pixels of the display visible to the other eye of the viewing person. By isolating the pixels of the display visible to each eye, the two components of a stereoscopic image can be presented on the display.
Since an ordinary viewer's eyes are side-by-side and aligned horizontally, the array of lenses makes pixels visible according to horizontal orientation. As a result, corresponding pixels for the left and right eyes are located in the same scanline and displaced from one another horizontally.
In the case of an autostereoscopic display having only two views, each eye of the viewer therefore sees an image having a horizontal resolution that is halved. In autostereoscopic displays, field of view may be improved by having more than just two views. Multiple view lenticular systems have at least four and some have 9 or more views, resulting in a reduction in horizontal resolution as perceived by the viewing person to one-fourth, one-ninth, or less of the original resolution. At the same time, the vertical resolution of the image as perceived by the viewer remains unchanged, resulting in an unpleasant and noticeable imbalance in the horizontal and vertical resolutions of the displayed image.
Further, to provide greater perceived depths of projection, many more views (for example, 24 views) are required within a relatively narrow space (for example, 1 mm). A typical LCD display screen may, for example, have a pixel density of about 200 pixels per inch, though some have densities approaching 300 or even 500 pixels per inch, depending on application. Such a pixel density corresponds to approximately 6 pixels per millimeter (that is, about one quarter of the resolution required to provide 24 views in a 1 mm space) to 20 pixels per millimeter. In general, many conventional video display devices are incapable of providing enough views in a sufficiently small space to satisfy the demands of modern autostereoscopic images.
In addition to LCD- and LED-based displays, opto-electronic displays that make use of organic materials are becoming increasingly desirable for a number of reasons. Many of the materials used to make such devices are relatively inexpensive and are highly efficient, so organic opto-electronic devices have the potential for cost advantages and power and other performance advantages over inorganic devices such as LEDs and LCDs. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on a flexible substrate. Examples of organic opto-electronic devices include organic light emitting devices (OLEDs). For OLEDs, the organic materials may have performance advantages over conventional materials. For example, the wavelength at which an organic emissive layer emits light may generally be readily tuned with appropriate dopants.
OLEDs make use of thin organic films that emit light when voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat panel displays, illumination, and backlighting. Several OLED materials and configurations are described in U.S. Pat. Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.
Phosphorescent emissive molecules are used in full color displays. Industry standards for such a display call for pixels adapted to emit particular colors, referred to as “saturated” colors. In particular, these standards call for saturated red, green, and blue pixels. Color may be measured using CIE coordinates, which are well known to the art.
One example of a green emissive molecule is tris(2-phenylpyridine) iridium, denoted Ir(ppy)3, which has the following structure:

In this structure, we depict the dative bond from nitrogen to metal (here, Ir) as a straight line.
As used herein, the term “organic” includes polymeric materials as well as small molecule organic materials that may be used to fabricate organic opto-electronic devices. “Small molecule” refers to any organic material that is not a polymer, and “small molecules” may actually be quite large. Small molecules may include repeat units in some circumstances. For example, using a long chain alkyl group as a substituent does not remove a molecule from the “small molecule” class. Small molecules may also be incorporated into polymers, for example as a pendent group on a polymer backbone or as a part of the backbone. Small molecules may also serve as the core moiety of a dendrimer, which consists of a series of chemical shells built on the core moiety. The core moiety of a dendrimer may be a fluorescent or phosphorescent small molecule emitter. A dendrimer may be a “small molecule,” and it is believed that all dendrimers currently used in the field of OLEDs are small molecules.
As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from substrate. There may be other layers between the first and second layer, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.
As used herein, “solution processible” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.
More details on OLEDs, and the definitions described above, can be found in U.S. Pat. No. 7,279,704, which is incorporated herein by reference in its entirety.